The present invention relates in general to systems and methods for sharing telecommunications lines and, more particularly, to systems and methods for providing voice and data services on the shared line and to permit full spectrum testing of the shared line to the voice and data service providers.
In November 1999, the Federal Communications Commission (FCC) in the United States ruled that Incumbent Local Exchange Carrier (ILECs) must share lines with any Competitive Local Exchange Carrier (CLECs). The goal was to provide consumers with a cost-effective solution for receiving differentiated data services. The ruling (FCC 99-355) allowed ILECs to maintain the low frequency portion of the telecom line providing voice transmission and for CLECs to use the high frequency segment for data access solutions.
Splitters are required to separate the higher frequency portion of the line going to the CLEC collocation from the low frequency portion being used by the ILEC. This arrangement hampered the CLECs from performing full spectrum voice and data testing on the local loop. On the other hand, ILECs are concerned that testing by CLECs might interfere with the ILECs Plain Old Telephone Service (POTS).
In a non-line sharing environment, the CLEC and ILEC each have full-spectrum test access to their respective lines. Since each ILEC has full control over its copper lines, the ILEC can test the local loop for bridge taps, coils and other anomalies that are critical to reliable analog voice transmission and the CLEC can fully test the local loop for parameters that are critical for high-speed data transmission.
However, under the November line-sharing ruling, the ILEC is required to allow the CLEC to share the existing lines to allow it to provide high speed data service on the same line that the ILEC is providing its POTS service. The splitter is a piece of equipment that allows this to happen.
The splitter allows the CLEC to provide high-speed data service to the local loop but blocks it from providing POTS service that is handled by the ILEC. The splitter allows the ILEC to provide POTS voice service but blocks it from providing high speed data service.
The problem is that although the CLEC might not need to provide POTS service, it needs to perform tests at low frequencies. The presence of a splitter prevents the CLEC from conducting low-frequency testing that is crucial to qualifying the line for DSL services. The splitter may be located either in the CLEC collocation (COLLO) or in the ILEC central office (CO) as shown in the diagrams below.
For example, if the splitter is located in the ILEC CO, then the CLEC cannot conduct low frequency testing to ensure that there are no bridge taps or coils on the line. The presence of the taps and coils although not a problem to the ILEC""s POTS service, is a major problem for the CLECs who can not test the low-frequency portion of the local loop. In order for line-sharing to work, the CLEC must have full-spectrum test-access to the shared line.
Local loop testing is a function that both CLEC and ILEC want to be able to do remotely. With the splitter in place, if a problem with the local loop arises, the CLEC can only perform high frequency tests, thus preventing it to determine the source of the problem. In order to diagnose a problem the CLEC or ILEC is forced to send a technician to the CO to insert a tester before the line is split. This significantly increases the delay and cost in deploying DSL and other high-speed services.
Accordingly, there is a need for a solution that would allow the CLEC and ILEC to perform line testing on the unfiltered local loop via remote control and to circumvent the splitter for testing purposes. There is a further need for CLEC testing to be performed in a manner that does not interfere with normal operation of voice telephone service provided by the ILEC. There is still a further need for a solution which may be easily deployed and maintained.
According to the present invention, a cross connect physical layer switching system is integrated into either the CLEC COLLO or the ILEC CO. The cross connect physical layer switching system may be used to facilitate aspects of delivering data services, such as digital subscriber line (DSL) service, to subscribers over a shared data and voice line. For example, the cross connect physical layer switching system may be used for service provisioning, test access for loop qualification, service migration and fallback switching to help reduce the deployment and maintenance time for high-speed data services.
The cross connect physical layer switching system may be placed between a splitter and the shared line to allow a remote test unit to be controllably connected to the shared line to permit testing of the shared line by the CLEC. By placing the physical layer switching system in the CO, both parties have full access to the test head or Remote Test Unit (RTU) and full spectrum testing of the line. This allows test access to continue to be done remotely as in an unshared line environment. The splitter problem is circumvented to allow both the CLEC and ILEC to have full-spectrum test access to the shared local loop. The result is shorter service deployment time, minimization of xe2x80x9ctruck rollsxe2x80x9d and more effective maintenance of the shared local loop. It also allows existing equipment to be used, thereby minimizing the investment costs needed by the Telecommunications Service Providers in order to overcome the technical obstacles of line-sharing.
To protect the ILEC, the CLEC may be provided with limited cross connect access only to shared lines. In order to protect against off-hook interference (such as interfering with a subscriber phone conversation) while the CLEC is qualifying a line for DSL services, the physical layer switching system and the remote test unit cooperate to prevent the test head from being connected to a line if the line is off-hook. When the line goes on-hook, the path to the line by the test head may be enabled. This allows the ILEC to comply with the FCC November ruling and provide full test access capability to the CLEC.
According to one embodiment of the invention, a method of providing shared data and voice service over a telecommunications line includes providing separate voice and data paths, providing a splitter having ports coupled to the separate voice and data paths and a port that represents a combination of signals on the first and second ports, and providing a cross connect switch that controllably connects the splitter to a shared line in a first state and a test unit to the shared line in a second state. Further steps include monitoring the shared line and testing the shared line when the line is on-hook.
The voice path occupies low frequencies of the shared line and the data path occupies high frequencies of the shared line. An ILEC may maintain the voice path and a CLEC the data path. In addition, either the CLEC or the ILEC may provide the cross connect switch and the splitter.
According to another embodiment of the invention, a system provides shared data and voice service over a telecommunications line. The system includes a splitter and a cross connect switch. The splitter has ports coupled to separate voice and data paths and an output that represents a combination of signals on the ports. The cross connect switch controllably connects the splitter to a shared line in a first state and a test unit to the shared line in a second state. The system may further include a controller coupled to the cross connect switch that controls the controllable connections. The controller may be coupled to the cross connect switch via a local or wide area network.